Experts don’t advise that young children get tested for a well-known breast cancer gene mutation. But if mothers are tested, should they tell their kids, who have a chance of carrying the same mutation?

In a study involving 221 mothers in the study led by researchers at Georgetown Lombardi Comprehensive Cancer Center, most mothers who learned they carried the BRCA1 or BRCA2 mutations, which heightens their risk for developing breast and ovarian cancer, chose to tell their children of their results. These women also reported feeling more at ease with their decision to share information compared to mothers who kept quiet.

The women were provided with genetic counseling both before and after getting the BRCA test, and also answered questions about their decisions to disclose the results, as well as their satisfaction with that decision. Not surprisingly, the moms, whose children ranged in age from 8 to 21, tended to be more forthcoming with older children. Overall, 62% of the mothers told their kids about their BRCA status, expressing feelings of relief at doing so but also reporting that they simply felt obliged to let their children know.

“Mothers who don’t discuss their results with their kids are relatively less satisfied and feel more conflicted,” says Kenneth Tercyak, director of behavioral prevention research at Georgetown Lombardi and lead author of the study published in the journal Cancer Epidemiology, Biomarkers & Prevention.

Moms were three times as likely to share reassuring results — tests that were negative for the mutations, or were uninformative and did not identify known genetic aberrations — than mothers who received positive results. “That patients were more likely to share the ‘good’ news with their child that a risk-conferring mutation in BRCA1/2 was not found upon genetic testing is consistent with other positive parenting practices,” write the authors. They likely felt that testing negative also reassured their children, who themselves would have an elevated risk of having inherited the mutations if their mothers carried them.

Less than 10% of women with breast cancer have a BRCA mutation, but doctors recommend that women with a family history of breast cancer be tested for the genetic abnormality, since intervention with drug treatments, surgery or a combination of both can prolong survival. The scientists were interested in understanding what factors influenced women to share test results, particularly with their children, who might also be affected by the cancer-conferring genes. “We were interested in what influences women to want to share test results,” says Tercyak. “It is not a black and white issue.”

At what age should mothers share such information with their children? It’s a mistake to use a child’s age alone as a guide when determining whether to share test results, say experts. As with so many other issues — such as the sex talk, for example — it’s important to consider maturity and a particular child’s readiness to understand complex subjects. Timing is also a factor. “We encourage women to spend time with a genetic counselor or doctor talking about this,” says Tercyak. “If they decide it’s a conversation they want to have, when is the right time?”

While the timing of such a talk can vary from family to family, the genetics and pediatrics community are more adamant about another sensitive issue involving genetic testing — when to test children. In February, the American Academy of Pediatrics and the American College of Medical Genetics and Genomics recommended that minors not be genetically tested for DNA-based diseases unless there is a health-related reason to do so. The experts concluded that there is generally no compelling reason for a child born to a mother or father with a BRCA mutation to be tested until at least age 18, when treatments options can be discussed.

In writing about the policy, I spoke to pediatricians and ethicists who laid out their reasons for the advice:

But what about parents who decide they want to test their kids just to know more about their children’s genetic predispositions? Curiosity alone is not enough reason for a physician to order a genetic test, according to the statement. Testing should be reserved to diagnose conditions and to pave the way for possible treatments. “We are not doing it just because parents have a right to do it,” says Dr. Lainie Friedman Ross, a professor of pediatrics and clinical ethics at the University of Chicago and the statement’s lead author. “The only reason we should recommend testing is because it would serve the medical best interests of the child.”

Lisa Schlager agrees with that thinking. Schlager, 46, learned at Georgetown in 1999, before she had children, that she has a defective BRCA gene. She waited until last year, when her daughter was 12, to explain that aspect of her family’s history. Schlager, an executive at Facing Our Risk of Cancer Empowered (FORCE), reassured her daughter that she had nothing to worry about as a child; there would be time enough when she became a young woman to learn more about her personal genetic blueprint. Schlager hasn’t yet told her son, who is 10. “He is not quite ready to have all the information yet,” she says. But when he is, she plans to discuss it with him.